/*
 * @(#) $Header$
 *
 * Copyright (C) 2007  Daniel Léonard
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

package ca.forklabs.baselib.util.function;

import ca.forklabs.baselib.util.BinaryFunction;

/**
 * Class {@code Project1stFunction} is a binary function that always returns its
 * first argument. It is an <em>identity</em>-like function for binary
 * functions.
 *
 * @param   <A1>   the type of the first argument object, and the type of the
 *                 returned object.
 * @param   <A2>   the type of the second argument object.
 *
 * @author   <a href="mailto:forklabs at gmail.com?subject=ca.forklabs.baselib.util.function.Project1stFunction">Daniel Léonard</a>
 * @version $Revision$
 */
public class Project1stFunction<A1, A2> implements BinaryFunction<A1, A1, A2> {

   /**
    * Always return the first argument.
    * @param   arg1   the first argument.
    * @param   arg2   ignored.
    * @return   {@code arg1}.
    */
   @Override
   public A1 invoke(A1 arg1, A2 arg2) {
      return arg1;
      }

   }
